As technology has advanced, the computational power of computers has increased while the size of computers has decreased. This has led to the use of computers in a wider range of fields and environments. One such use for computers is as a replacement for traditional paper-based books. Rather than having the text and illustrations of a book printed on paper, computers allow such text and illustrations to be stored digitally and displayed on a screen of the computer. Such current uses for computers, however, are not without their problems. One such problem is that current user interfaces for books can be cumbersome and non-intuitive, which can result in user frustration when using computers for reading books.